1. Field of the Invention
This invention relates to an image forming apparatus such as an electronic copying machine capable of preventing unauthorized copying (unauthorized use) and totalizing the number of copied sheets for each user, for example.
2. Description of the Related Art
Conventionally, a key counter is used or an ID code (personal identification information) is registered as a means for monitoring the number of copied sheets and preventing the unauthorized copying. The key counter permits the copying machine to be set into the operative state when it is attached to the copying machine and it counts the number of copied sheets (the number of image forming operations). In the ID code registration method, the copying machine is set into the operative state when the user inputs the previously registered ID code by means of the operation panel and the number of copied sheets (the number of image forming operations) is counted for each ID code.
However, when the number of copied sheets is monitored and totalized for each user by use of the key counter, a key counter must be prepared and monitored for each user. In this case, it is difficult to totalize the number of copied sheets for each relatively short period of time, for example, for each day or for each month.
In the ID code registration method, the number of copied sheets can be monitored and totalized for each day for each user. In this case, since a key is not used, even an unauthorized person can use the copying machine if a registered ID code is input via the operation panel, and this is not preferable from the viewpoint of the operation of monitoring and totalizing the number of copied sheets.
Further, the number of copied sheets cannot be totalized for each paper size.
The technique of using a card with the ID function and counting the number of copied sheets for each card (for each ID card) or counting the number of copied sheets for each paper size is known as the technique using a card. However, the technique is based on a reading system for magnetically or optically reading the signal inherent to the card by the copying machine body or an exclusive device connected to the copying machine and the counts of the respective numbers of copied sheets are stored into the copying machine body or the exclusive device connected to the copying machine. Therefore, when the counts of the respective numbers of copied sheets are totalized by use of a personal computer, for example, the personal computer must be connected to the copying machine to transfer the count data from the copying machine to the personal computer.